Engineers create a real-life tractor beam, but it only manipulates tiny particles

Why it matters: Just like teleportation, cloning, and invisibility, tractor beams are one of those sci-fi movie tropes many of us have wished were real. But thanks to some researchers at MIT, we now have a miniaturized version small enough to fit on a single chip. While it can't pull entire ships as shown in Star Wars just yet, it can still manipulate biological particles like cells and DNA.

MIT has created a chip-based optical tractor beam that can focus a penetrating beam of light over 5 millimeters away from the surface of the chip itself. That might not sound like much, but it's a game-changer compared to previous integrated "optical tweezers" that could only work within a few microns of the chip. Those older approaches essentially had to remove cells from their sterile glass containers (used commonly for biological experiments) and place them directly on the chip's surface, raising contamination risks.

The breakthrough changes those limitations. With its extended range, MIT's device can precisely trap and move around biological samples through the glass, while they stay sealed off in standard cover slip containers. The process keeps everything clean and sterile.

As for how the micro tractor beam works, it hinges on a silicon photonics component called an integrated optical phased array. This uses an array of microscopic antennas fabricated on a chip using semiconductor manufacturing processes. These antennas can collectively shape and steer a focused beam just by adjusting the timing of the optical signals driving each antenna element.

According to the team, as noted in an MIT press release, this system is "an improvement of several orders of magnitude higher compared to prior demonstrations."

Another major improvement is that this new system shrinks tractor beam capabilities down to chip proportions for the first time. Typical designs for the same purpose not only have a limited range but are rather bulky and require a large microscope setup in a lab, as well as multiple devices to form and control light.

To validate their invention, the MIT engineers started by using the chip to capture and manipulate tiny polystyrene spheres (a reference particle used in experiments). Once they had that working, they leveled up to trapping and moving around living cancer cells.

Although still in the early stages, the potential implications are huge across biological research and even clinical applications. The beam can be used to analyze DNA, classify cells, study the mechanics of diseases, and for all kinds of new experiments and diagnostic tools.

The researchers want to keep evolving the system, too, with goals such as adding adjustable beam focus, using multiple trap sites simultaneously, and applying it to different bio-systems.